1. Field of the Invention
The present invention is generally related to a lubrication system of a marine propulsion device and, more particularly, to a lubrication system that facilitates the removal and replacement of lubricating oil from a marine drive unit that is suspended below the generally horizontal hull surface of a marine vessel.
2. Description of the Related Art
Those skilled in the art of marine propulsion systems are aware of many different types of lubrication systems that store and provide lubricating oil to various portions of the engine and drive unit of the marine propulsion device. As will be described in greater detail below, some marine propulsion devices present unique and difficult problems because of the location and configuration of the marine drive unit in relation to the marine vessel with which it is associated.
U.S. Pat. No. 4,397,198, which issued to Borgersen et al. on Aug. 9, 1983, describes a marine transmission assembly system. A reversing double cone clutch drive assembly for a boat comprising a horizontal input shaft, a vertical intermediate output shaft, a first housing provided with an opening in a side wall opposite to the input shaft and an opening in a bottom wall through which the lower end of said intermediate output shaft is exposed, and selectable gear transmission subassemblies attachable to such clutch drive assembly, each subassembly including a second housing with a generally horizontal wall for engaging such bottom wall, said second housing carrying a bearing which mounts an output shaft driven through gear means by the intermediate output shaft said housing being filled interiorly with lubricating oil, in heat exchange relationship with cooling water exterior of the housing are described.
U.S. Pat. No. 4,875,884, which issued to Meisenburg on Oct. 24, 1989, discloses a marine propulsion device with a through transom engine oil drain system. A fluid flow tube is provided which extends from the lower portion of an engine oil pan to a point on the boat transom below the pan. The upper end portion of the tube is connected through a control valve which communicates with the pan interior. The lower or discharge tube end portion is connected through a fitting extending through the transom. A removable plug is associated with the fitting and, when removed, permits oil to drain out through the transom and into an oil collection receptacle when the control valve is open.
U.S. Pat. No. 4,913,109, which issued to Slattery on Apr. 3, 1990, discloses a marine outboard drive with oil tank fill tube. It includes a two-cycle internal combustion engine, an oil storage tank storing lubricating oil for the engine, and a fill tube within the engine cowl for filling the oil tank there-below. The fill tube includes a partitioned upper cup portion vented to the tank and closed by a tactiley hinged cap.
U.S. Pat. No. 4,986,777, which issued to Preston on Jan. 22, 1991, describes a marine engine oil drainage device. A discharge device includes a tubular casing which is snugly disposed within the drainage port in the stern of the vessel. The casing is hollow and has an exterior and an interior. The walls of the casing have drainage openings for allowing water in the bottom of the vessel to drain into the casing and out of the vessel via the drainage port.
U.S. Pat. No. 5,284,223, which issued to Fisher on Feb. 8, 1994, describes an apparatus and method for venting and for monitoring oil levels in marine outdrives. It includes an oil monitoring reservoir suitable for locating inside the boat. The reservoir is in fluid communication with a fully oil flooded head of the marine outdrive. The reservoir can be observed for an indication of oil level and oil condition. A clear plastic oil reservoir may be used to enhance visual observation.
U.S. Pat. No. 5,487,687, which issued to Idzikowski et al. on Jan. 30, 1996, discloses a midsection and cowl assembly for an outboard marine drive. The midsection housing includes an oil sump in one embodiment and further includes an exhaust passage partially encircled by cooling water and partially encircled by engine oil for muffling engine exhaust noise. The midsection housing has an oil drain arrangement providing complete and clean oil draining while the outboard drive is mounted on a boat and in the water wherein the operator can change oil without leaving the confines of the boat and entering the water.
U.S. Pat. No. 5,899,779, which issued to Hattori on May 4, 1999, describes an oil system drain for a personal watercraft. The drain arrangement is provided for a lubricating system of an engine powering a watercraft. The engine is mounted to a hull of the watercraft and includes a lubricating system having a lubricant collector positioned at a bottom of the engine and a lubricating system drain also positioned at the bottom of the engine through which lubricant may be drained from the collector.
U.S. Pat. No. 6,132,275, which issued to Tanaka et al. on Oct. 17, 2000, describes a lubricating oil managing arrangement for an outboard marine drive engine. A tubular socket member is sealingly fitted into an opening formed on one side of the crankcase of the engine at a level corresponding to a normal engine lubricating oil level and a transparent window member is sealingly fitted into an outer end of the tubular socket member. An engine cover covering the engine is provided with an opening aligned with the transparent window member so as to allow the level of lubricating oil in the crankcase to be inspected from outside the engine cover.
U.S. Pat. No. 6,575,797, which issued to Martin et al. on Jun. 10, 2003, discloses an oil drain system for an outboard motor. It provides an oil drain opening formed in a lower surface of the splash plate of the outboard motor at a location which allows oil to drain from the oil drain opening under the force of gravity in a downward direction without contacting any surfaces of the outboard motor. This allows the oil to be received by a waste oil container that is placed at any point directly below the oil drain opening, either on the ground below the gear case of the outboard motor or at any point that is vertically below the oil drain opening.
U.S. Pat. No. 6,655,341, which issued to Westerbeke on Dec. 2, 2003, describes an oil sump for vertically shafted engines. It has a housing with an upper face for sealing against a block of the engine. The sump housing defines an internal volume for containing a quantity of oil received from the engine through an oil drain opening in the upper face of the sump and defines an exhaust inlet for receiving a flow of exhaust from the engine and directing the flow of exhaust toward an exhaust outlet along an exhaust passage defined within the housing.
U.S. Pat. No. 6,755,704, which issued to Leinonen on Jun. 29, 2004, describes an oil tank drain system for a watercraft. It includes an oil reservoir coupled to a flow regulator located in the interior of the personal watercraft. The flow regulator is additionally coupled to a cover that seals an axis opening formed on the exterior of the personal watercraft by means of a tether such that when the cover is removed for an oil change the tether pulls the flow regulator to the exterior of the watercraft so that oil in the reservoir can be drained to the exterior of the watercraft.
U.S. Pat. No. 6,837,210, which issued to Tsuchiya et al. on Jan. 4, 2005, describes a lubrication unit for engines. An oil feed pump for feeding oil in an oil tank to an engine, an oil recovery pump for feeding oil in a crankcase into the oil tank, an oil drainpipe connected to the lower portion of the crankcase and extending upward, and an opening provided on top of the oil tank are provided in a lubrication system. An opening of the oil drain pipe opens at the position upward of the oil level in the crankcase at a moment when the oil in the oil tank is returned into the crankcase. A cap is provided with a dipstick. The engine can be mounted on a small planing boat with the crankshaft oriented in the fore and aft direction. The oil tank is integrally formed with the front portion of the engine so as to be elongated in the vertical direction and is formed with the opening on top.
U.S. Pat. No. 7,033,234, which issued to Arvidsson et al. on Apr. 25, 2006, describes a method of steering a boat with double outboard drives and boat having double outboard drives. The outboard drive units with underwater housings extend down from the bottom of the boat. When running at planing speed straight ahead, the underwater housings are set with “toe-in”. When turning, the inner drive is set with a greater steering angle than the outer drive unit.
U.S. Pat. No. 7,118,434, which issued to Arvidsson et al. on Oct. 10, 2006, describes an outboard drive for boats. It includes an underwater housing in which two propeller shafts are mounted and are driven via a first bevel gearing enclosed in the underwater housing and a second bevel gearing enclosed in a gear housing. With the aid of a mounting element joined to the underwater housing and the gear housing, the drive unit can be mounted in an opening in the bottom of a boat hull with the underwater housing on the outside of the gear housing on the inside of the hull. The mounting element forms a housing which defines firstly an oil reservoir for the oil of the drive unit and secondly a surrounding chamber through which engine cooling water flows and which is used for cooling the oil in the reservoir.
U.S. Pat. No. 7,131,385, which issued to Ehlers et al. on Nov. 7, 2006, discloses a method for braking a vessel with two marine propulsion devices. It comprises the steps that rotate two marine propulsion devices about their respective axes in order to increase the hydrodynamic resistance of the marine propulsion devices as they move through the water with the marine vessel. This increased resistance exerts a braking thrust on the marine vessel. Various techniques and procedures can be used to determine the absolute magnitudes of the angular magnitudes by which the marine propulsion devices are rotated.
U.S. Pat. No. 7,182,657, which issued to Mansson on Feb. 27, 2007, describes a boat hull with outboard drive and outboard drive for boats. The boat hull comprises an outboard drive unit, which comprises an underwater housing mounted on the outside of the hull bottom and a gear housing mounted on the inside of the hull bottom and joined to the underwater housing. Between the underwater housing and the gear housing there is fixed a mounting plate which together with a screw-down plate with elastic ring inserts fixes the drive unit to a flange which is made on the inside of a well surrounding an opening in the hull bottom.
U.S. Pat. No. 7,186,157, which issued to Mansson et al. on Mar. 6, 2007, describes a turning propeller drive for a boat. The propeller drive includes an upper fixing plate adapted for a rotational fixed attachment to the hull bottom of the boat. A lower underwater housing is provided in which at least one propeller is mounted which underwater housing is mounted rotatably in the fixing plate about an essentially vertical axis of rotation. An exhaust duct is provided with an exhaust exit located in the underwater housing. The exhaust duct has an upper duct section which extends through the fixing plate and has an outlet opening located in proximity to an opposite inlet opening in a lower duct section which extends through the underwater housing. One of the outlet opening and inlet opening overlaps the other at least within a limited first rotational angle range for the propeller drive. A sliding seal arrangement is adapted for sealing between the upper and lower duct sections, where the sliding seal arrangement includes a sealing element accommodated in a seat around one of the outlet opening and inlet opening.
U.S. Pat. No. 7,188,581, which issued to Davis et al. on Mar. 13, 2007, discloses a marine drive with an integrated trim tab. A marine drive and a marine vessel and drive combination have a trim tab with a forward end pivotally mounted to a marine propulsion device.
U.S. Pat. No. 7,234,983, which issued to Davis on Jun. 26, 2007, discloses a protective marine vessel and drive. A marine vessel and drive combination includes port and starboard tunnels formed in a marine vessel hull raising port and starboard steerable marine propulsion devices to protective positions relative to the keel.
U.S. Pat. No. 7,267,068, which issued to Bradley et al. on Sep. 11, 2007, discloses a method for maneuvering a marine vessel in response to a manually operable control device. A marine vessel is maneuvered by independently rotating first and second marine propulsion devices about their respective steering axes in response to commands received from a manually operable control device, such as a joystick. The marine propulsion devices are aligned with their thrust vectors intersecting at a point on a centerline of the marine vessel and, when no rotational movement is commanded, at the center of gravity of the marine vessel. Internal combustion engines are provided to drive the marine propulsion devices. The steering axes of the two marine propulsion devices are generally vertical and parallel to each other. The two steering axes extend through a bottom surface of the hull of the marine vessel.
The patents described above are hereby expressly incorporated by reference in the description of the present invention.
Removing oil from an oil sump of a marine propulsion device typically uses a discharge port that is at or near the lowest portion of the oil sump. Then, with the aid of gravity, the oil can be allowed to flow out of the marine drive unit into an appropriate container to collect the used oil from the drive unit and dispose of it. This procedure becomes much more complex when the drive unit is located below the hull of a marine vessel. Certain types of marine propulsion systems incorporate rotatable drive units that extend downwardly from the hull of the marine vessel. Systems of this type are described in U.S. Pat. Nos. 7,033,234 and 7,182,657 which are described above. In addition, marine propulsion systems with drive units that extend downwardly below the hull of a marine vessel are described in U.S. Pat. Nos. 7,188,581 and 7,234,983.
It would be significantly beneficial if an efficient and effective way of removing oil from drive units in marine propulsion systems that are located below the hull of a marine vessel could be provided.